The results of the Phase I effort, during the course of which the blood samples of 7 HbSS patients were examined, established the feasibility of using phase-sensitive acoustic detection techniques to quantitatively monitor the polymerization of HbSS. The effects of introducing anti-sickling agents were also clearly resolved in the results. In addition, the acoustic measurements performed on 5 normal blood samples revealed the techniques sensitivity by demonstrating the reproducible resolution of the minute acoustic response to de-oxygenation of normal blood. With the basic response question settled, the primary aim of the Phase II effort will be to develop a laboratory prototype that can be used by a third party to support anti-sickling drug research efforts, general sickle cell research, as well as be potentially used as a potential diagnostic tool in clinical settings. In order to accomplish this goal, the following specific aims will be pursued under Phase II: 1. An improved experimental prototype will be designed. 2. A stable and repeatable test substrate (cell suspension) will be developed. 3. The device will be characterized extensively with regard to calibration, sensitivity, and sample variability. 4. The effects of an extensive number of anti-sickling agents will be measured. PROPOSED COMMERCIAL APPLICATION: Not Available